Hi,I've done a lot of research into medieval dyes, but I can't find much on their storage. Were they stored, or were they made and used immediately? If they were stored, what materials and objects would have been used?

Speaking for the 12th century, the implication of available evidence is that dyes were not stored as such, but used continuously, sometimes for weeks, with vats being kept simmering and cloth (and other materials such as wood and leather) being dyed in huge quantities. John of Garland reports that the dyer had tubs or vats which he heated over a fire. His common dyes were woad, madder and graine; a dyer was a marked man because of the permanent stains under his fingernails.

The dye plants would need to be stored in bulk, along with salt, wood ash and any other ingredients, but my own view I that the dye itself was used long-term, then a new batch was produced.

A London Guild of Dyers existed in the 12th century (mentioned in a document of 1188) and this meant a monopoly on industrial-scale dying. This would not rule out small-scale local dying using hedgerow plants, but to quote "The Medieval Dyer": Dye recipes and access to imported dye plants were jealously guarded by the medieval dyers' guilds and it was not until 1548 that a book containing dye recipes first became available to the general public.

I have used chopped madder which I bought in bulk, to dye wool in a cauldron over a fire in demonstrations at events. I have also collected black crottal (a kind of lichen, which gives the most wonderful smell to the finished product!)

While I am being educated by the history (above), for my own use in re-enactment, I keep my dyestuffs in small wooden boxes. Interestingly enough, when I store the boxes between seasons, the mice don's see interested... not a nibble.

Wooden boxes, pouches, pottery vessels. The unused dyestuff would be kept in whatever people had. Of course, once in solution it would be used and thrown away after. I am not aware of any archaeological excavationn finding artefacts which have dye residues in them, but I certainly haven't read all available excavation reports, and not enough scientific excavation happens either.